1. Isolation is just that - good. nothing special and there are others that isolate better, but let me say this - I commute a lot too, and never had any problems with isolation.
2. they can be won overear but I'd rather not :D too uncomfortable and weird looking :)
3. build looks really great. I doubt anything could happen with it anytime soon...
4. I actually think that for that kind of money, especially for Germany, these are really good. I think you'd have to pay double to gt the same level of quality...
5. never had a xears so I can not comment on that. but these are really great, with big, clean sub-bass and awesome mids, with relaxed highs.
Thank you for your input, appreciate it! One follow-up question: if overear is not an option, how bad would you say the microphonics are?
Btw: I just looked up the price for the EPH-100 and they would actually cost double, so your estimate seems spot on ;)